The blue LED comes on when there is an active Bluetooth connection. Make sure location services are turned on when you are trying to use the app, it absolutely will not work without it. It's an Android thing not an app thing.
If they are going to go on the roof bifacial is a waste of your money, however there are less tariffs on those, so they may end up being very close to the same price as regular panels.
Next train of thought has to be what inverter fits your needs....what are your needs and desires ?
Maybe an...
If you can replace the inverter dirt cheap then I would do that, you could probably find a working used same or similar model if you hunt around. But after that you might as well go ahead and replace the panels too because they are low powered compared to what you can get today.
I would not put damaged or under 300w panels on a roof. Mine are 4yr old Panasonic 330w panels.
Yep I got to the point in life where I have more money than time.
AC, DC, high voltage, low voltage can all be mixed in the same metal trunk/wireway as long as all wire insulation is rated for the maximum voltage carried.
Also I think it should be ok to wire to the latest code even if your AHJ doesn't enforce it yet, but double check with them. Your's seem...